Chemistry · Chemical Reactions

Reaction Heat & pH Lab Simulation

Run both reactions below just like the bench lab: pour the reactant, test its pH, trigger the reaction, and watch the thermometer while the timer logs a reading every 15 seconds for 2.5 minutes. Use the data table and graph you build to decide which reaction released heat and which one absorbed it.

Materials

2 beakersYeastGoggles ThermometerHydrogen peroxideCups VinegarClockBaking soda Plastic beakerScaleHot tap water pH strips

Key vocabulary

  • Celsius scale — temperature scale where water freezes at 0°C and boils at 100°C
  • Exothermic reaction — releases energy in the form of heat
  • Endothermic reaction — absorbs energy in the form of heat
  • Chemical change — substances combine or break apart to form new substances
  • pH — a measure of how acidic or basic a substance is

Run the reactions

Work through each station's steps in order. Every station keeps its own timer, thermometer and pH strip.

Playback speed applies to any station that is currently timing a reaction.

Temperature Measurements

Time (min)Part 1 (°C)Part 2 (°C)

Temperature vs. Time

Part 1 · H₂O₂ + Yeast Part 2 · Vinegar + Baking Soda

Run each station just like the bench lab, then use what you recorded to answer the questions in the other tab.

  1. 1Follow the steps in order. Each station lists its next action with a 🥽 marker — click the highlighted button to perform that step.
  2. 2Test pH whenever the button appears. The colored strip and number update to show whether the substance is acidic, neutral, or basic.
  3. 3Starting the reaction starts the timer. Once you add the yeast or baking soda, the clock and thermometer run on their own — watch the readout for the live temperature.
  4. 4Choose your playback speed in the bar above the data table: real time matches the 2.5-minute lab exactly, fast-forward compresses it to about 25 seconds.
  5. 5Watch the table and graph fill in automatically every simulated 15 seconds, just like you would record it by hand in the lab.
  6. 6Hover over the graph to read exact temperatures at any time for both reactions at once.
  7. 7Use "Reset" on a station to run that reaction again, or "Reset both stations" to start the whole simulation over.
  8. 8Answer the questions in the "Questions to answer" tab — your typed answers are saved automatically in this browser.